[libshumate] demos: Add ShumateTestTileSource

[Marcus Lundblad <mlundblad src gnome org>]

commit 923faf48c7351377bde720e41eb2cd1e44ccfbc9
Author: James Westman <james jwestman net>
Date:   Sat Feb 27 21:44:52 2021 -0600

    demos: Add ShumateTestTileSource
    
    Add a test pattern option to the demo. This tile source generates a test
    pattern designed to help debug tile placement. It also provides an
    example of custom map sources and how to switch between map styles.

 demos/meson.build                |   1 +
 demos/shumate-demo-window.c      |  82 +++++++++++++++++++++++-----
 demos/shumate-demo-window.ui     |  17 ++++++
 demos/shumate-test-tile-source.c | 115 +++++++++++++++++++++++++++++++++++++++
 demos/shumate-test-tile-source.h |  32 +++++++++++
 5 files changed, 234 insertions(+), 13 deletions(-)
---
diff --git a/demos/meson.build b/demos/meson.build
index 7085e40..b1c4851 100644
--- a/demos/meson.build
+++ b/demos/meson.build
@@ -9,6 +9,7 @@ shumate_demo_sources = [
 
   'shumate-demo.c',
   'shumate-demo-window.c',
+  'shumate-test-tile-source.c',
 ]
 
 shumate_demo = executable(
diff --git a/demos/shumate-demo-window.c b/demos/shumate-demo-window.c
index 640e965..d34a686 100644
--- a/demos/shumate-demo-window.c
+++ b/demos/shumate-demo-window.c
@@ -17,6 +17,8 @@
 
 
 #include "shumate-demo-window.h"
+#include "shumate-test-tile-source.h"
+
 
 struct _ShumateDemoWindow
 {
@@ -25,9 +27,13 @@ struct _ShumateDemoWindow
   ShumateView *view;
   GtkOverlay *overlay;
   ShumateLicense *license;
+  GtkDropDown *layers_dropdown;
 
+  ShumateMapLayer *tile_layer;
   ShumateMarkerLayer *marker_layer;
   ShumatePathLayer *path_layer;
+
+  ShumateMapSource *current_source;
 };
 
 G_DEFINE_TYPE (ShumateDemoWindow, shumate_demo_window, GTK_TYPE_APPLICATION_WINDOW)
@@ -56,40 +62,86 @@ create_marker (ShumateDemoWindow *self, double lat, double lng)
 }
 
 
+static void
+set_map_source (ShumateDemoWindow *self, ShumateMapSource *new_source)
+{
+  ShumateViewport *viewport = shumate_view_get_viewport (self->view);
+  ShumateMapLayer *tile_layer;
+
+  if (self->current_source) {
+    shumate_license_remove_map_source (self->license, self->current_source);
+  }
+
+  g_clear_object (&self->current_source);
+  self->current_source = new_source;
+
+  shumate_viewport_set_reference_map_source (viewport, new_source);
+  shumate_view_set_map_source (self->view, new_source);
+
+  tile_layer = shumate_map_layer_new (new_source, viewport);
+  shumate_view_insert_layer_behind (self->view, SHUMATE_LAYER (tile_layer), SHUMATE_LAYER 
(self->tile_layer));
+  if (self->tile_layer) {
+    shumate_view_remove_layer (self->view, SHUMATE_LAYER (self->tile_layer));
+  }
+  self->tile_layer = tile_layer;
+
+  shumate_license_append_map_source (self->license, new_source);
+}
+
+static void
+on_layers_dropdown_notify_selected (ShumateDemoWindow *self, GParamSpec *pspec, GtkDropDown *dropdown)
+{
+  g_autoptr(ShumateMapSourceFactory) factory = NULL;
+
+  switch (gtk_drop_down_get_selected (dropdown)) {
+  case 0:
+    factory = shumate_map_source_factory_dup_default ();
+    set_map_source (self, shumate_map_source_factory_create_cached_source (factory, 
SHUMATE_MAP_SOURCE_OSM_MAPNIK));
+    break;
+  case 1:
+    set_map_source (self, SHUMATE_MAP_SOURCE (shumate_test_tile_source_new ()));
+    break;
+  }
+}
+
+
+static void
+shumate_demo_window_finalize (GObject *object)
+{
+  ShumateDemoWindow *self = SHUMATE_DEMO_WINDOW (object);
+
+  g_clear_object (&self->current_source);
+
+  G_OBJECT_CLASS (shumate_demo_window_parent_class)->finalize (object);
+}
+
+
 static void
 shumate_demo_window_class_init (ShumateDemoWindowClass *klass)
 {
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
   GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
 
+  object_class->finalize = shumate_demo_window_finalize;
+
   gtk_widget_class_set_template_from_resource (widget_class, 
"/org/gnome/Shumate/Demo/ui/shumate-demo-window.ui");
   gtk_widget_class_bind_template_child (widget_class, ShumateDemoWindow, view);
   gtk_widget_class_bind_template_child (widget_class, ShumateDemoWindow, overlay);
   gtk_widget_class_bind_template_child (widget_class, ShumateDemoWindow, license);
+  gtk_widget_class_bind_template_child (widget_class, ShumateDemoWindow, layers_dropdown);
+  gtk_widget_class_bind_template_callback (widget_class, on_layers_dropdown_notify_selected);
 }
 
 
 static void
 shumate_demo_window_init (ShumateDemoWindow *self)
 {
-  g_autoptr(ShumateMapSourceFactory) factory = NULL;
-  g_autoptr(ShumateMapSource) map_source = NULL;
-  ShumateMapLayer *layer;
   ShumateScale *scale;
   ShumateViewport *viewport;
 
   gtk_widget_init_template (GTK_WIDGET (self));
 
-  factory = shumate_map_source_factory_dup_default ();
-  map_source = shumate_map_source_factory_create_cached_source (factory, SHUMATE_MAP_SOURCE_OSM_MAPNIK);
-  shumate_view_set_map_source (self->view, map_source);
-
   viewport = shumate_view_get_viewport (self->view);
-  shumate_viewport_set_reference_map_source (viewport, map_source);
-
-  layer = shumate_map_layer_new (map_source, viewport);
-  shumate_view_add_layer (self->view, SHUMATE_LAYER (layer));
-
-  shumate_license_append_map_source (self->license, map_source);
 
   scale = shumate_scale_new (viewport);
   g_object_set (scale,
@@ -98,6 +150,10 @@ shumate_demo_window_init (ShumateDemoWindow *self)
                 NULL);
   gtk_overlay_add_overlay (self->overlay, GTK_WIDGET (scale));
 
+  /* Set the map source */
+  on_layers_dropdown_notify_selected (self, NULL, self->layers_dropdown);
+
+  /* Add the marker layers */
   self->marker_layer = shumate_marker_layer_new (viewport);
   shumate_view_add_layer (self->view, SHUMATE_LAYER (self->marker_layer));
   self->path_layer = shumate_path_layer_new (viewport);
diff --git a/demos/shumate-demo-window.ui b/demos/shumate-demo-window.ui
index eb2edc9..6bb2a59 100644
--- a/demos/shumate-demo-window.ui
+++ b/demos/shumate-demo-window.ui
@@ -6,8 +6,19 @@
     <property name="title" translatable="yes">Shumate Demo</property>
     <property name="default_width">800</property>
     <property name="default_height">600</property>
+    <child type="titlebar">
+      <object class="GtkHeaderBar">
+        <child>
+          <object class="GtkDropDown" id="layers_dropdown">
+            <property name="model">layers</property>
+            <signal name="notify::selected" handler="on_layers_dropdown_notify_selected" swapped="true" />
+          </object>
+        </child>
+      </object>
+    </child>
     <child>
       <object class="GtkOverlay" id="overlay">
+        <property name="vexpand">True</property>
         <child>
           <object class="ShumateView" id="view">
           </object>
@@ -21,4 +32,10 @@
       </object>
     </child>
   </template>
+  <object class="GtkStringList" id="layers">
+    <items>
+      <item translatable="yes">Mapnik (OSM)</item>
+      <item translatable="yes">Test Pattern</item>
+    </items>
+  </object>
 </interface>
diff --git a/demos/shumate-test-tile-source.c b/demos/shumate-test-tile-source.c
new file mode 100644
index 0000000..0ff847c
--- /dev/null
+++ b/demos/shumate-test-tile-source.c
@@ -0,0 +1,115 @@
+/*
+ * Copyright (C) 2021 James Westman <james jwestman net>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <https://www.gnu.org/licenses/>.
+ */
+
+
+#include "shumate-test-tile-source.h"
+
+struct _ShumateTestTileSource
+{
+  ShumateTileSource parent_instance;
+};
+
+G_DEFINE_TYPE (ShumateTestTileSource, shumate_test_tile_source, SHUMATE_TYPE_TILE_SOURCE)
+
+
+ShumateTestTileSource *
+shumate_test_tile_source_new (void)
+{
+  return g_object_new (SHUMATE_TYPE_TEST_TILE_SOURCE, NULL);
+}
+
+
+static GdkTexture *
+texture_new_for_surface (cairo_surface_t *surface)
+{
+  g_autoptr(GBytes) bytes = NULL;
+  GdkTexture *texture;
+
+  g_return_val_if_fail (cairo_surface_get_type (surface) == CAIRO_SURFACE_TYPE_IMAGE, NULL);
+  g_return_val_if_fail (cairo_image_surface_get_width (surface) > 0, NULL);
+  g_return_val_if_fail (cairo_image_surface_get_height (surface) > 0, NULL);
+
+  bytes = g_bytes_new_with_free_func (cairo_image_surface_get_data (surface),
+                                      cairo_image_surface_get_height (surface)
+                                      * cairo_image_surface_get_stride (surface),
+                                      (GDestroyNotify) cairo_surface_destroy,
+                                      cairo_surface_reference (surface));
+
+  texture = gdk_memory_texture_new (cairo_image_surface_get_width (surface),
+                                    cairo_image_surface_get_height (surface),
+                                    GDK_MEMORY_B8G8R8A8_PREMULTIPLIED,
+                                    bytes,
+                                    cairo_image_surface_get_stride (surface));
+
+  return texture;
+}
+
+
+static void
+shumate_test_tile_source_fill_tile (ShumateMapSource *map_source,
+                                    ShumateTile      *tile,
+                                    GCancellable     *cancellable)
+{
+  g_autoptr(GdkTexture) texture = NULL;
+  guint tile_size = shumate_tile_get_size (tile);
+  int x = shumate_tile_get_x (tile), y = shumate_tile_get_y (tile);
+  int zoom = shumate_tile_get_zoom_level (tile);
+  int max_zoom = shumate_map_source_get_max_zoom_level (map_source);
+  cairo_surface_t *surface;
+  cairo_t *cr;
+  float r, g, b;
+  g_autofree char *text = NULL;
+
+  g_return_if_fail (SHUMATE_IS_TEST_TILE_SOURCE (map_source));
+  g_return_if_fail (SHUMATE_IS_TILE (tile));
+
+  surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, tile_size, tile_size);
+  cr = cairo_create (surface);
+
+  gtk_hsv_to_rgb (zoom / (double) max_zoom, 1, ((x + y) % 2 == 0) ? 1 : 0.5, &r, &g, &b);
+  cairo_set_source_rgb (cr, r, g, b);
+  cairo_paint (cr);
+
+  cairo_set_source_rgb (cr, 0, 0, 0);
+  cairo_move_to (cr, 8, tile_size - 8);
+  cairo_scale (cr, 2, 2);
+  text = g_strdup_printf ("%d, %d (z%d)", x, y, zoom);
+  cairo_show_text (cr, text);
+
+  texture = texture_new_for_surface (surface);
+  cairo_surface_destroy (surface);
+  cairo_destroy (cr);
+
+  shumate_tile_set_texture (tile, texture);
+  shumate_tile_set_fade_in (tile, TRUE);
+  shumate_tile_set_state (tile, SHUMATE_STATE_DONE);
+}
+
+
+static void
+shumate_test_tile_source_class_init (ShumateTestTileSourceClass *klass)
+{
+  ShumateMapSourceClass *map_source_class = SHUMATE_MAP_SOURCE_CLASS (klass);
+
+  map_source_class->fill_tile = shumate_test_tile_source_fill_tile;
+}
+
+
+static void
+shumate_test_tile_source_init (ShumateTestTileSource *self)
+{
+}
diff --git a/demos/shumate-test-tile-source.h b/demos/shumate-test-tile-source.h
new file mode 100644
index 0000000..8a17d44
--- /dev/null
+++ b/demos/shumate-test-tile-source.h
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2021 James Westman <james jwestman net>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <https://www.gnu.org/licenses/>.
+ */
+
+
+#pragma once
+
+#include <glib-object.h>
+#include <shumate/shumate.h>
+
+G_BEGIN_DECLS
+
+#define SHUMATE_TYPE_TEST_TILE_SOURCE (shumate_test_tile_source_get_type())
+
+G_DECLARE_FINAL_TYPE (ShumateTestTileSource, shumate_test_tile_source, SHUMATE, TEST_TILE_SOURCE, 
ShumateTileSource)
+
+ShumateTestTileSource *shumate_test_tile_source_new (void);
+
+G_END_DECLS